EDINBURGH — Researchers at the University of Edinburgh have found that higher skeletal muscle density, observed in chest and back scans, is associated with a reduced risk of heart attack and death over a 10-year period. The findings were published in the journal Radiology.

The study utilized artificial intelligence to examine hospital scans from 1,722 patients, predominantly in their 50s, who had presented with chest pain. Patients demonstrating greater muscle density in their chests and backs were less likely to experience a heart attack or death in the decade following their scans.

Artificial intelligence was employed to analyze skeletal muscle attenuation, which refers to the brightness or darkness of muscle in a scan. Denser muscle appears lighter in an X-ray image due to more X-ray beams reflecting off it. For every 10-point increase in scan brightness, individuals were found to be 31% less likely to have a heart attack and 39% less likely to die within 10 years after the scan. The study indicated that the overall size of a person's muscles was not linked to their risk of heart attack or early death.

Professor Michelle Williams, a senior author of the study, said, "It is fascinating that people's skeletal muscle could be linked to their risk of having a heart attack." She identified the muscles observed in the coronary computed tomography angiogram scans as primarily back muscles, parts of the pectoral muscles, and the intercostal muscles between the ribs. "The muscles which show up in the scans we used – coronary computed tomography angiogram scans – are principally the back muscles, part of the pectoral muscles – or 'pecs' – and the intercostal muscles between the ribs," Williams said. "So I am now personally interested in exercises like cycling, planks and pilates, which I enjoy and may have an effect on these muscles." She added, "However, we need far more research to better understand how exercise may affect muscle density, and how this may relate to heart health."

The British Heart Foundation provided partial funding for the study. Professor Bryan Williams, Chief Scientific and Medical Officer at the British Heart Foundation, commented on the findings. "It is likely that people in this study with more dense muscle mass were more physically active and as a result may have better heart health," he said. "That is yet more evidence supporting the power of exercise."